Membranes may be used to perform osmosis, which generally occurs when two solutions of differing concentration are placed on opposite sides of a permeable or semi-permeable membrane. The osmotic pressure difference between the two solutions drives the permeation of water across the membrane from the dilute solution to the concentrated solution, while the selective property of the membrane retains the solutes in their respective solution.
Plate and frame separation elements may generally include a plate and frame for enclosing a stack or array of membrane plate assemblies. Plate and frame separation elements may include a combination of a flat sheet membrane, a draw channel spacer, a flat sheet membrane, and feed channel spacer.